Q To-Do is a work-in-progress on porting To-Do-O to Qt/QML.
Currently Q To-Do supports the basic features for handling a to-do list, such as: adding new, editing, deleting, or moving entries.
A sync functionality as in To-Do-O is currently missing. So you need to manually copy your existing data from e.g. your N900 or PC to your N9/N950.
You can download Q To-Do from my repository.